Full electric vehicle with multi-speed transmission: a review on dynamic and energetic performances improvements

Abstract

Multi-speed transmissions (MSTs) can improve the dynamic and energetic performance of battery electric vehicles (BEVs), but their benefits depend on transmission architecture, gear ratios, shift strategy and losses.This paper presents a comprehensive literature review and quantitative database of published BEV MST studies, comparing dynamic and energetic performance with single-speed transmissions (SSTs). The results show that MSTs do not inherently provide simultaneous improvements.Walker et al. reported 19.4% faster 0–60 km/h acceleration, 47% higher top speed and 80% higher gradeability, but an 8–10% driving- range penalty. Conversely, Ruan et al. achieved 13.7% faster 0–60 km/h acceleration, 61.6% higher top speed, 25% higher gradeability and 30.9% lower energy consumption using a CVT. Tian et al. reported a 29.4% reduction in energy consumption with a 4-speed transmission and moderate dynamic improvements. The results highlight the importance of transmission efficiency, gear-ratio selection and shift strategy, rather than the number of ratios alone. A dynamic–energetic trade-off framework is proposed to support the multi-objective selection and optimization of MST configurations for BEVs.